I want to know where to find the information about the code structure of any debian package like e.g bash,gawk,grep or any other package. If we open the source code directory we find some similar folders in each of them like m4,po or tests etc. what every folder is meant for ? Specially the "tests" folder ,can we test each package with this "tests" folder.Simply i want to know all information for source code packages.

Welcome to LQ.

Example gawk_4.1.4+dfsg.orig.tar.xz :
"orig" means it's at large the author´s original source code. Not Debian.

m4 :
Is an 'Autotools' component. Autotools is on of the ~10 ways to build source code.
Autotools http://www.gnu.org/software/automake...roduction.html

Other common source code configuration / build methods:
cmake, qmake, 'python setup.py build', scons, './waf configure', jam, bjam, 'perl Makefile.PL', 'perl Build.PL', ant, mvn, etc.

About test / tests :
Many different versions / ways of tests : Please read the documentation for the particular application / library.

po : Language files (translations), for the languages included in po/.


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$ apt-file list devscripts | grep -i bin/
$ sudo apt-get install devscripts

Running man on most of those should help you understand things more. Recalling a dev update track at a linux con a couple years back and rmadison.

There are many ways to build .deb packages. The one way I understand is the fakeroot variant.

$ fakeroot ./debian/rules binary

Do the ./configure steps first and you can customize things. It will build the .deb's in the parent directory so be a bit further down the line than $HOME/. But there's lots of odd ducks and that method applies to maybe 50% of the sources (if I was an optimist).

That is too big of a question. The answer would be meaningless. Debian uses the gnu toolchain and the Debian build system. So, the contents of a Debian source package are either source code, or something to do with the gnu chain or Debian build scripts. If you want further detail, google one of those and then ask something more specific.